Centering device.



C. D. MCARTHUR. l CENTERING DEVICE. 4 APPLICATIQN FILED M Avzs. 1911.l

131,234,543, s PatentedApr.6,1915.-

2 SHEETS-SHEET 2.

I tions 'of the CHARLES D. MCARTHUR, or PTTSBURGH, PENNSYLVANIA,

As'sIGNon To BLAW A CORPORATION OF NEW JEBSEY.

CENTERING DEVICE TOaZZ whom t may concern Be it known that I, CHARLES D. M0- AR'rHUR, a citizen of the United States, re. siding lat Pittsburgh, in the county of Allegheny and State of Pennsylvania, have 1nvented certain new and useful Improvements in Centering Devices, of which the following is a specification.

The invention relates to steel collapsible centering devices or forms, for the use in the construction of sewers, aqueducts and the like, and particularly to forms intended for relativelylarge work, in which the secforms are designed tovtelescope inside of each other during the construction of the conduit or sewer.

The invention has for its primary obj ects; the provision of a form of large size which shall be self supporting without the use of transverse braces when in operative position, so that an unobstructed space is ali'orded for the passage of other forms therethrough; the provision of a construction which may be readily collapsed and moved from place to place; and the provisions of 4improved means for handling the forms and moving them from place to place.

One embodiment of the invention is -illustrated in the accompanying drawings, wherein a Figure 1 isy a transverse section through my improved form of mold with the concrete applied thereover, the dotted lines showing the position of the walls of the form when in collapsed position, and Fig. 2 is a longitudinal section through the center of the mold at right angles to the section of Fig. 1.

The walls of the form consist of sheet metal lagging plates 1 stiii'ened and s'upported by means of sti'ening ribs 2, preferably T irons, to which the plates 1 are bolted. The ribs 2 are placed near enough together to give the form the necessary sti'ness, and to make the form self supporting without the necessity of transverse braces. In order to permit the kform to collapse, the three hinges 3, 4 and 5 are provided, the hinge 3 permitting the top sections 6 and 7 to swing toward each other, and the hinges 4 and 5 permitting the Alower sectionsY or wings 8 and 9 to swing up tothe position indicated in dotted lines, when it is desired to move the form to anew location.

In order to collapsesthe form and move it ySpecification of Letters Patent.

' whereby Patented Apr. e, i915.

Application led May 25, 1911. Serial No. 629,441.

from place to place, the truck 10 moving on the rails l1 is provided," such truck or traveler being provided with a plurality of hydraulic jacks or rams 12, v13 and 14 for moving the sections of the form. As indicated in Fig. 2, the pistons offthe'ram's 12 are provided with the engaging brackets 15, adapted to engage'the hinges 3 at the top of the form. 'Ihe cylinders 13 and 14 are provided with the piston rods 16, 17 eX- tending clear through the cylinders as indicated in Fig. 1. he front ends of these piston rods are adapted to be secured to the brackets 18 and 19 carried by the T irons 2, whilethe rear ends of these piston rods are adapted to besecured by means of ropes or other fiexible members 20 to the lower sections 8 and 9.

In collapsing one of the shells, the timbers 21 and 22 are first removed, and the lower sections 8 and 9 are swung into the position indicated in dotted lines by means of the cable connections from the rear ends of the pistons 16 and 17. After the sections 8 and 9 have been secured in collapsed posiy illustrated its use, what I claim as new and desireto secure by Letters Patent is the following l. The com ination with a collapsible mold open at the bottom and comprising a pair of top sections having -a hinged connection at their upper edges, and a second i pair of sections hinged to the lower edges of the irst sections, the sections being stiiiened by ribs and so arranged that the mold will maintain. itself in expanded position and permit the passage therethrough ofv a truck carrying another mold, of a truck, and mechanism carried thereby the top sections may be moved up and down and movedvabout their hinged connection toexpanded or working position.

2. In combination in a conduit mold, open at the bottom and-having curved sides, a pair of top sections having -a hinge connection at their upper edges, and a second pair of sections hinged to the lower edges of the 4irst sections, sti'ening ribs carried by the sections, a truck, and mechanism carried by the truck and adapted to raise and lower the top sections and to swing such sections out.- ward to expanded position, the connection atthe hinged edges and the shape and curve of the sections being such that the mold is self supporting and unobstructed and permits the passage therethrough of la truck carrying another mold.

In testimony whereof have hereunto l5 signed'my name in the presence of the two subscribed witnesses. i

CHARLES D. MCARTHUR.

Witnesses:

DOERING BELLINGER, JULIAN H. KENDIG. 

